Fan

ABSTRACT

A fan includes a frame, an impeller, and a motor. The impeller includes a hub, blades, and air-guiding plates. The hub has a tapered shape and the width of the hub gradually increases. The hub has an air vent. The blades are disposed around the outer periphery of the hub. The air-guiding plates are disposed around the inner periphery of the hub. The motor is disposed in the frame, and connects to and drives the impeller to rotate. The motor includes a stator structure and a rotor structure. The rotor structure includes a shaft, a magnetic conductive housing, and a magnetic element. One end of the shaft connects to the magnetic conductive housing. The magnetic element is disposed around the inner periphery of the magnetic conductive housing and located corresponding to the stator structure. The top surface of the magnetic conductive housing has at least one opening.

CROSS REFERENCE TO RELATED APPLICATIONS

This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 201810664160.4 filed in People'sRepublic of China on Jun. 25, 2018, the entire contents of which arehereby incorporated by reference.

BACKGROUND OF THE INVENTION Field of Invention

The present disclosure relates to a fan and, in particular, to a mixedflow fan with an enhanced heat dissipation efficiency inside the fan.

Related Art

As the increasing of the performance of electronic devices, a lot ofwaste heat can be generated during the operation of the electronicdevices. If the generated heat cannot be brought away the electronicdevices, the temperature of the electronic devices will increase, whichmay cause the damage of the internal components and decrease theperformance and lifetime of the electronic device. A fan is generallyused as the heat-dissipation device in the electronic device. Recently,a fan (a mixed flow fan) having blades and hub with two or moredifferent diameters is disclosed. However, although the conventionalmixed flow fan is benefit in the heat dissipation of electronic device,the selection of the motor in the fan is highly limited to the materialsdue to the geometrical shape thereof. If the high-power heat dissipationis required, the selection of silicon steel plates may result in morewaste heat accumulated inside the fan. This will cause the overheatinginside the fan and lead to the burning of circuit board or thesufficient decreasing of the fan operation performance, therebyaffecting the heat dissipation efficiency and lifetime of the fan.

Therefore, it is desired to provide a mixed flow fan that has anenhanced heat dissipation efficiency itself, thereby preventing theoverheating inside the fan, and thus extending the lifetime of the fanand maintaining the fan operation efficiency.

SUMMARY OF THE INVENTION

An objective of this disclosure is to provide a fan that has an enhancedheat dissipation efficiency itself, thereby extending the lifetime ofthe fan and maintaining the fan operation efficiency.

This disclosure provides a fan, which comprises a frame, an impeller anda motor. The impeller comprises a hub, a plurality of blades, and aplurality of air-guiding plates. The hub has a tapered shape. A width ofthe hub gradually increases along a direction from a top portion of thehub to a bottom portion of the hub, and the hub has at least an airvent. The blades are disposed around an outer periphery of the hub, andthe air-guiding plates are disposed around an inner periphery of thehub. The motor is disposed in the frame and comprises a stator structureand a rotor structure. The motor connects to and drives the impeller torotate. The rotor structure comprises a shaft, a magnetic conductivehousing, and a magnetic element. One end of the shaft connects to themagnetic conductive housing. The magnetic element is disposed around aninner periphery of the magnetic conductive housing and locatedcorresponding to the stator structure. A top surface of the magneticconductive housing has at least an opening.

In one embodiment, the air vent is disposed on the top portion of thehub.

In one embodiment, the air vent is disposed between the top portion ofthe hub and front edges of the blades contacting the outer periphery ofthe hub.

In one embodiment, a size of the air vent is greater than or equal to 3mm, or an equivalent area of the entire air vent is greater than orequal to 7 mm².

In one embodiment, the frame comprises a base, and a distance between atop portion of the base and the bottom portion of the hub is greaterthan or equal to 1.0 mm.

In one embodiment, each air-guiding plate extends from the innerperiphery of the hub to an axis of the hub.

In one embodiment, a ratio of a height of each air-guiding plate to adistance from the top portion of the hub to the bottom portion of thehub ranges from 0.3 to 1.2.

In one embodiment, a ratio of a length of each air-guiding plate to adiameter of the magnetic conductive housing ranges from 0.1 to 0.9.

In one embodiment, the length of each air-guiding plate is greater thanor equal to 10 mm, and a distance between each air-guiding plate and anaxis of the hub is greater than or equal to 4 mm.

In one embodiment, a thickness of each air-guiding plate is greater thanor equal to 1.0 mm.

In one embodiment, each air-guiding plate has a rib shape or a wingshape.

In one embodiment, the air-guiding plates are arranged with equivalentinterval angles.

In one embodiment, the air-guiding plates are arranged with inequivalentinterval angles.

In one embodiment, the air-guiding plates have the same lengths,thicknesses, heights, or shapes.

In one embodiment, at least one of lengths, thicknesses, heights, orshapes of the air-guiding plates are different.

In one embodiment, the inner periphery of the frame is configured withan air-guiding curved surface disposed at an air inlet side of the fan.

As mentioned above, in the fan of this disclosure, the heat dissipationefficiency inside the fan can be enhanced by providing at least one airvent on the hub, disposing a plurality of air-guiding plates around theinner periphery of the hub, and configuring at least one opening at thetop surface of the magnetic conductive housing. Compared with theconventional fan, the fan of this disclosure can enhance the heatdissipation efficiency itself, thereby extending the lifetime of the fanand maintaining the fan operation efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thesubsequent detailed description and accompanying drawings, which aregiven by way of illustration only, and thus are not limitative of thepresent invention, and wherein:

FIG. 1 is a schematic diagram showing a fan according to an embodimentof this disclosure;

FIG. 2 is a sectional view of the fan of FIG. 1;

FIG. 3 is a side view of the fan of FIG. 2;

FIG. 4 is a schematic diagram showing the impeller of the fan of FIG. 2;

FIG. 5A is a schematic diagram showing an impeller of the fan accordingto an embodiment of this disclosure;

FIG. 5B is a schematic diagram showing another impeller of the fanaccording to another embodiment of this disclosure;

FIG. 5C is a schematic diagram showing another impeller of the fanaccording to another embodiment of this disclosure;

FIG. 5D is a schematic diagram showing another impeller of the fanaccording to another embodiment of this disclosure; and

FIG. 6 is a schematic graph showing the temperature distribution of thefans of different embodiments of this disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be apparent from the following detaileddescription, which proceeds with reference to the accompanying drawings,wherein the same references relate to the same elements.

A fan of this disclosure can enhance the heat dissipation efficiencyitself, thereby extending the lifetime of the fan and maintaining thefan operation efficiency. The structure and features of fan of thisdisclosure will be described in the following embodiments.

FIGS. 1 to 4 are schematic diagrams showing a fan 1 according to anembodiment of this disclosure. Referring to FIGS. 1 to 4, the fan 1comprises a frame 11, an impeller 12 and a motor 13. The inner peripheryof the frame 11 is configured with an air-guiding curved surface 11 adisposed at an air inlet side F of the fan 1 for increasing the totalair inlet area and guiding the air flow. The fan 1 of this disclosureis, for example, a mixed flow fan, but this disclosure is not limitedthereto.

Referring to FIGS. 2 to 4, the impeller 12 comprises a hub 121, aplurality of blades 122, and a plurality of air-guiding plates 123. Thehub 121 has a tapered shape. A width of the hub 121 gradually increasesalong a direction from a top portion 1211 of the hub 121 to a bottomportion 1212 of the hub 121, and the hub 121 has at least an air vent1213. In this embodiment, the air vent 1213 is a through hole, so thatthe airflow can pass through the air vent 1213. The blades 122 aredisposed around an outer periphery of the hub 121, and the air-guidingplates 123 are disposed around an inner periphery of the hub 121. Inparticular, as shown in FIGS. 2 to 4, the hub 121 has an extensionportion 1214 protruding from the bottom portion 1212. To be noted, theextension portion 1214 of the hub 121 can also be evened with the bottomportion 1212 of the hub 121, and this disclosure is not limited thereto.

As shown in FIGS. 2 and 3, the motor 13 is disposed in the frame 11 andconnects to and drives the impeller 12 to rotate. The motor 13 comprisesa stator structure 131 and a rotor structure 132. The rotor structure132 comprises a shaft 1321, a magnetic conductive housing 1322, and amagnetic element 1323. One end of the shaft 1321 connects to themagnetic conductive housing 1322. The magnetic element 1323 is disposedaround an inner periphery of the magnetic conductive housing 1322 andlocated corresponding to the stator structure 131. A top surface of themagnetic conductive housing 1322 has at least an opening 13221. Theopening 13221 is a through hole, so that the air flow can pass throughthe opening 13221. In particular, the end portion the shaft 1321 or theregion close to the end portion of the shaft 1321 (the end portionprotrudes from the magnetic conductive housing 1322, not shown) isconnected to the magnetic conductive housing 1322. This disclosure isnot limited thereto. In addition, the amount and shape of the opening13221 can be modified based on the actual requirement of the user, andthis disclosure is not limited. When the motor 13 drives the impeller 12to rotate, the operation will generate waste heat accumulated inside themotor 13. The opening 13221 disposed on the top surface of the magneticconductive housing 1322 allows the air to flow into the motor 13 fordissipating the waste heat, thereby enhancing the heat dissipationefficiency itself. In particular, the stator structure 131 of the motor13 can be composed of silicon steel plates, coil, or other materials,and this disclosure is not limited. Moreover, FIGS. 2 and 3 show thatthe bottom portion of the magnetic conductive housing 1322 protrudesfrom the bottom portion 1212 of the hub 121. To be noted, the bottomportion of the magnetic conductive housing 1322 may even with the bottomportion 1212 of the hub 121 (not shown), and this disclosure is notlimited thereto.

With Reference to FIGS. 2 and 3, the fan 1 further comprises a circuitboard 14 electrically connected with the stator structure 131 fordriving the stator structure 131.

In this embodiment, for example, the hub 121 comprises one air vent1213. The air vent 1213 is disposed on the top portion 1211 of the hub121, and the air vent 1213 faces toward the air inlet side F of the fan1. Since the air vent 1213 is designed as a through hole, the air flowcan pass through the air vent 1213 and reach inside the hub 121.Besides, the configuration of the air-guiding plates 123 can increasethe air flowing inside the hub 121, thereby enhancing the heatdissipation efficiency itself. In particular, the amount and shape ofthe air vent 1213 can be modified based on the actual requirement of theuser, and this disclosure is not limited.

In another embodiment, at least one air vent 1213 is disposed betweenthe top portion 1211 of the hub 121 and the front edges 121 a of theblades 122 contacting the outer periphery of the hub 121. For example,as shown in FIG. 4, the air vent 1213 can be disposed on any positionwithin the region defined by the line b, which is between the topportion 1211 of the hub 121 and the front edges 121 a of the blades 122contacting the outer periphery of the hub 121. As mentioned above, whenthe air vent 1213 is disposed in front of the front edges 121 a of theblades 122, it is benefit to guide the air flow into the hub 121. If theair vent 1213 is disposed at the position other than the above preferredregion, the air flow may be guided to the air outlet directly aftercontacting the blades 122, and will not enter the hub 121.

Referring to FIGS. 2 and 3, in this embodiment, the frame 11 comprises abase 111, and a distance d (as shown in FIG. 3) between a top portion1111 of the base 111 and the bottom portion 1212 of the hub 121 isgreater than or equal to 1.0 mm. The configuration of the distance d canprevent the collision between the impeller 12 and the base 111 as wellas the generated noise during the operation. In addition, theconfiguration of the distance d can also increase the exchange betweenthe airflows inside and outside the impeller 12, so that the waste heatgenerated by the motor 13 can be dissipated to the outside. This canfurther enhance the heat dissipation efficiency of the fan 1 itself. Asshown in FIGS. 2 and 3, the other end of the shaft 1321 can be connectedto the base 111.

FIGS. 5A to 5D are schematic diagrams showing different impellers 12according to different embodiments of this disclosure. Referring toFIGS. 4 and 5A to 5D, the size r1 of the air vent 1213 of the impeller12 is greater than or equal to 3 mm, or an equivalent area of the entireair vent 1213 (the total area of the entire air vent 1213) is greaterthan or equal to 7 mm². The air vent 1213 is a through hole, and theairflow can pass through the air vent 1213. As shown in FIGS. 4 and 5Ato 5D, for example, the impeller 12 comprises an air vent 1213, and theair vent 1213 is a circular hole disposed on the top portion 1211 of thehub 121. The size r1 is greater than or equal to 3 mm, which means thediameter r1 of the circular hole is greater than or equal to 3 mm.Alternatively, an equivalent area of the entire air vent 1213 is greaterthan or equal to 7 mm², which means the total area of the entirecircular hole is greater than or equal to 7 mm². In particular, theamount and shape of the air vent 1213 can be modified based on theactual requirement of the user, and this disclosure is not limited. Tobe noted, the air vent 1213 can be disposed between the top portion 1211of the hub 121 and the front edges 121 a of the blades 122 contactingthe outer periphery of the hub 121 (see FIG. 4), and this disclosure isnot limited. For example, if the air vent 1213 is a rectangular hole,the size r1 is greater than or equal to 3 mm, which means the length r1of the air vent 1213 is greater than or equal to 3 mm. Alternatively, anequivalent area of the entire air vent 1213 is greater than or equal to7 mm², which means the total area of the entire air vent 1213 is greaterthan or equal to 7 mm². If the air vent 1213 has an irregular shape, thesize r1 is greater than or equal to 3 mm, which means the diameter r1 ofthe average length r1 is greater than or equal to 3 mm. Alternatively,an equivalent area of the entire air vent 1213 is greater than or equalto 7 mm², which means the total area of the entire air vent 1213 isgreater than or equal to 7 mm².

As shown in FIG. 4, a ratio of a height h of each air-guiding plate 123to a distance H from the top portion 1211 of the hub 121 to the bottomportion 1212 of the hub 121 ranges from 0.3 to 1.2. In particular,although FIG. 4 shows that the air-guiding plates 123 are disposed alongthe direction D1 extending from the top portion 1211 of the hub 121 tothe bottom portion 1212 of the hub 121, the configuration of theair-guiding plates 123 can also be adjusted according to the requirementof the user, and this disclosure is not limited. For example, theair-guiding plates 123 can be disposed along a horizontal line having anincluded angle with the direction D1 extending from the top portion 1211of the hub 121 to the bottom portion 1212 of the hub 121.

The detailed configuration of the air-guiding plates 123 will bedescribed hereinafter with reference to FIGS. 4 and 5A to 5D. Herein,the air-guiding plates 123 are disposed along the direction D2 extendingfrom the inner periphery of the hub 121 to the axis c of the hub 121.That is, the direction D2 is perpendicular to the inner periphery of thehub 121. In particular, although FIG. 4 shows that the air-guidingplates 123 are disposed along the direction D2 perpendicular to theinner periphery of the hub 121 (the air-guiding plate 123 and the innerperiphery of the hub 121 have an included angle of 90 degrees), theair-guiding plate 123 and the inner periphery of the hub 121 may haveanother included angle (e.g. 20 degrees, 45 degrees, or other degrees).The configuration of the included angle therebetween can be adjustedaccording to the requirement of the user, and this disclosure is notlimited.

Referring to FIG. 5A in view of FIG. 3, in this embodiment, a ratio ofthe length m of each air-guiding plate 123 to the diameter r2 of themagnetic conductive housing 1322 ranges from 0.1 to 0.9.

Referring to FIG. 5A, in this embodiment, the length m of eachair-guiding plate 123 is greater than or equal to 10 mm, and a distancebetween each air-guiding plate 123 and an axis c of the hub 121 isgreater than or equal to 4 mm.

Referring to FIG. 5A, in this embodiment, a thickness w of eachair-guiding plate 123 is greater than or equal to 1.0 mm.

Referring to FIGS. 5A to 5C, each air-guiding plate 123 has a rib shapeor a wing shape. In particular, as shown in FIGS. 5A to 5C, theair-guiding plate 123 has a rib shape. Of course, the air-guiding plate123 may have a wing shape (not shown).

As shown in FIGS. 5A to 5C, the air-guiding plates 123 are arranged onthe inner periphery of the hub 121 with equivalent interval angles.Alternatively, the air-guiding plates 123 are arranged on the innerperiphery of the hub 121 with inequivalent interval angles.

Referring to FIGS. 5A to 5D in view of FIG. 4, the air-guiding plates123 may have the same or different lengths m, thicknesses w, heights h,or shapes. As shown in FIG. 5A, the lengths m, thicknesses w, heights h,or shapes of the air-guiding plates 123 are the same. As shown in FIG.5B, the air-guiding plates 123 have different length m and length m′. Asshown in FIG. 5C, the air-guiding plates 123 have different length m andlength m′, different thickness w and thickness w′, and different shapes.As shown in FIG. 5D, the air-guiding plates 123 have different length mand length m′, different thickness w and thickness w′, and differentshapes, and the air-guiding plates 123 are separately arranged withinequivalent interval angles. Of course, the air-guiding plates 123 mayhave different heights h (not shown). In particular, the intervalangles, lengths m, thicknesses w, heights h or shapes of the air-guidingplates 123 can be modified based on the actual requirement of the user,and this disclosure is not limited thereto. In this embodiment, theair-guiding plates 123 are configured for guiding the airflow from theair vent 1213 to the opening 13221 disposed on the top surface of themagnetic conductive housing 1322, thereby enhancing the heat dissipationefficiency of the fan itself and dissipating the waste heat out of themotor by the airflow.

FIG. 6 is a schematic graph showing the temperature distribution of thefans of different embodiments of this disclosure. Referring to FIG. 6 inview of FIG. 2, in this embodiment, the results of the heat dissipationefficiencies provided by four 92 mm×95 mm mixed flow fans (17500 RPM,240 W) are obtained. The results of the first fan (left-top of FIG. 6)and the second fan (right-top of FIG. 6) are used as the blanks data. Inthe first fan, the hub 121 is not configured with the air vent 1213 andthe air-guiding plates 123, and the internal temperature thereof is 247°C. (at the position of the motor 13 as shown in FIG. 2). In the secondfan, an air vent 1213 with a size of 3 mm is configured on the hub 121,and the hub 121 is not configured with the air-guiding plates 123. Theinternal temperature of the second fan is 179° C. (at the position ofthe motor 13 as shown in FIG. 2). In the third fan (left-bottom of FIG.6), an air vent 1213 with a size of 3 mm is configured on the hub 121,and the hub 121 is configured with the air-guiding plates 123. Theinternal temperature of the third fan is 135° C. (at the position of themotor 13 as shown in FIG. 2). In the fourth fan (right-bottom of FIG.6), an air vent 1213 with a size of 5 mm is configured on the hub 121,and the hub 121 is configured with the air-guiding plates 123. Theinternal temperature of the fourth fan is 99° C. (at the position of themotor 13 as shown in FIG. 2). In more detailed, in the fan of thisdisclosure, the hub 121 is configured with an air vent 1213, and theinner periphery of hub 121 is configured with air-guiding plates 123.This design can effectively decrease the inner temperature of the fan.In addition, the heat dissipation efficiency of the fan itself can befurther enhanced by increasing the size of the air vent 1213.

In summary, the fan 1 of this disclosure comprises at least one air vent1213 disposed on the hub 121, a plurality of air-guiding plates 123disposed on the inner periphery of the hub 121, and at least one opening13221 disposed on the top surface of the magnetic conductive housing1322. The air vent 1213 and the opening 13221 are through holes, so thatthe air flow can pass therethrough. Accordingly, the air flow can beguided from the hub 121 to the motor 13 through the opening 13221,thereby carrying the waste heat generated by the motor 13 away the fan1. In addition, the heat dissipation efficiency of the fan 1 itself canbe enhanced by configuring different sizes, scales or shapes of theair-guiding plates 123. Moreover, the distance d between the top portion1111 of the base 111 of the frame 11 and the bottom portion 1212 of thehub 121 is configured for further exchanging the hot air flow inside themotor and the outside air flow, thereby further enhancing the heatdissipation efficiency of the fan 1 itself.

Although the present invention has been described with reference tospecific embodiments, this description is not meant to be construed in alimiting sense. Various modifications of the disclosed embodiments, aswell as alternative embodiments, will be apparent to persons skilled inthe art. It is, therefore, contemplated that the appended claims willcover all modifications that fall within the true scope of the presentinvention.

What is claimed is:
 1. A fan, comprising: a frame; an impeller,comprising: a hub having a tapered shape, wherein a width of the hubgradually increases along a direction from a top portion of the hub to abottom portion of the hub, and the hub has at least an air vent, aplurality of blades disposed around an outer periphery of the hub, and aplurality of air-guiding plates disposed around an inner periphery ofthe hub; and a motor disposed in the frame, wherein the motor connectsto and drives the impeller to rotate, and the motor comprises: a statorstructure, and a rotor structure comprising a shaft, a magneticconductive housing, and a magnetic element, wherein one end of the shaftconnects to the magnetic conductive housing, the magnetic element isdisposed around an inner periphery of the magnetic conductive housingand located corresponding to the stator structure, and a top surface ofthe magnetic conductive housing has at least an opening.
 2. The fanaccording to claim 1, wherein a size of the air vent is greater than orequal to 3 mm, or an equivalent area of the entire air vent is greaterthan or equal to 7 mm².
 3. The fan according to claim 1, wherein the airvent is disposed on the top portion of the hub.
 4. The fan according toclaim 3, wherein a size of the air vent is greater than or equal to 3mm, or an equivalent area of the entire air vent is greater than orequal to 7 mm².
 5. The fan according to claim 3, wherein the air vent isdisposed between the top portion of the hub and front edges of theblades contacting the outer periphery of the hub.
 6. The fan accordingto claim 5, wherein a size of the air vent is greater than or equal to 3mm, or an equivalent area of the entire air vent is greater than orequal to 7 mm².
 7. The fan according to claim 1, wherein the framecomprises a base, and a distance between a top portion of the base andthe bottom portion of the hub is greater than or equal to 1.0 mm.
 8. Thefan according to claim 1, wherein each of the air-guiding plates extendsfrom the inner periphery of the hub to an axis of the hub.
 9. The fanaccording to claim 1, wherein a ratio of a height of each of theair-guiding plates to a distance from the top portion of the hub to thebottom portion of the hub ranges from 0.3 to 1.2.
 10. The fan accordingto claim 1, wherein a ratio of a length of each of the air-guidingplates to a diameter of the magnetic conductive housing ranges from 0.1to 0.9.
 11. The fan according to claim 10, wherein the length of each ofthe air-guiding plates is greater than or equal to 10 mm, and a distancebetween each of the air-guiding plates and an axis of the hub is greaterthan or equal to 4 mm.
 12. The fan according to claim 10, wherein athickness of each of the air-guiding plates is greater than or equal to1.0 mm.
 13. The fan according to claim 1, wherein each of theair-guiding plates has a rib shape or a wing shape.
 14. The fanaccording to claim 1, wherein the air-guiding plates are arranged withequivalent interval angles.
 15. The fan according to claim 1, whereinthe air-guiding plates are arranged with inequivalent interval angles.16. The fan according to claim 8, wherein the air-guiding plates havethe same lengths, thicknesses, heights, or shapes.
 17. The fan accordingto claim 8, wherein at least one of lengths, thicknesses, heights, orshapes of the air-guiding plates are different.
 18. The fan according toclaim 1, wherein the inner periphery of the frame is configured with anair-guiding curved surface disposed at an air inlet side of the fan.